Abstract: :
Purpose: To investigate the changes of cornea due to vitaminE deficiency and determine the effects of vitamin A supplementation.Methods: Male infant rats from normal mothers were weaned at20 days of age and divided into two groups: Group 1, E(-), ratswere fed a vitamin E-deficient diet; Group 2, E(-)A(+), ratswere fed a vitamin E-deficient diet and injected intraperitoneallywith 5000IU of vitamin E per 2 week. At 16 months of age, thecorneal changes of these rats were examined by scanning electronmicroscopy (SEM) and transmission electron microscopy (TEM).Results: The body weight between the two groups showed no significantdifference (P=0.0686, t-test comparison of means). The serumvitamin A level was significantly higher in the E(-)A(+) ratsthan that in the E(-) rats (P=0.0320, t-test comparison of means).SEM showed more fine microvilli and clear cells in the mostsuperficial epithelial layer of the cornea in the A(-)E(+) ratsthan in the E(-) rats. The surface of the cornea in the E(-)A(+)rats was smooth. But, the surface of the cornea in the E(-)rats was slightly rough and uneven. Some exfoliating cells wereseen in the cornea of the E(-) rats. TEM showed abnormal structuresin the E(-) rats. There are some high electron dense depositsin the subepithelial layer of the stroma in the E(-) rats. Thenumber of hemi-desmosomes in the E(-) rats was decreased. Onthe other hand, the epithelium in the E(-)A(+) rats looked normal.There were many light cells with numerous microvilli in themost superficial layer and many hemi-desmosomes at the basalcells in the E(-)A(+) rats.Conclusions: The present studysuggests that the cornea is obviously damaged by vitamin E-deficiencyand that vitamin A has a protective effect against the cornealdamages caused by vitamin E-deficiency.